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Is anyone making/selling the short barrels and jackets? Saw one at knob creek on the line and it looked cool.
 

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PhD in Over-Engineering
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Just for future reference, I have purchased barrel blanks in .30 cal, which are currently with one of the machine shops I work with. We are going to do the common operations for all Browning barrel configurations- threads, headspace notches (USGI style) and the air cooled bearing diameter full length. That way, we can keep half of them in said configuration for future determination as to the model. Meanwhile, we will have about half of them turned to standard A4, 1919A2 and 1917 configuration, maybe even a few A6. And we can custom do any length of air cooled style, as we can cut to desired length, crown, then just do the relief cut between the bearings. That makes these versatile. This is a little ways off yet, but the basic rifled and honed blanks are in hand. Also, we plan to have these Black Nitride finished, which greatly extends life.
 

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Does anyone know if the short barrels will work without have the bearing diameter at the end? In other words if you cut down a barrel, recrown it, and cut the angle will it function? I would assume if you had a smaller booster hole diameter it would make up for the gases that escape around the barrel.
 

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PhD in Over-Engineering
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They should work okay. The drawback to not having the full bearing diameter at the front is that this does, at least in theory, put more potential wear on the trunnion bearing area, due to the barrel being able to shift angle slightly. But how much this matters in real live, versus theory, is an open question. My skills as a mechanical engineer are rather limited. (Read: non-exixtent!)

But to your point, in my post above you will see that this is why my blanks will get left at full bearing diameter from the rear to the front, until final length is determined for a particular blank. That enables me to do, say, a 16" barrel and not have this issue. It's extra work to replace the original bearing end on a shortened barrel, but that is what most do.
 

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BeltFed GURU
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zammer217,
The issue is what a barrel like you propose does to the barrel extension , without proper support of the out board end of the barrel, it will rub in the trunnion and cock the barrel extension causing it to bind up the works so it will not function !
Even the M-2 style long barrels with the short shrouds were supported so every thing was kept in line and allowed it to function .
All you need to do is put a sleeve on the muzzle end of the cut barrel that is the same size as the original bearing surface ,i have two MG34 converted barrels that were sleeved fore and aft and the sleeves were drilled and roll pinned in place well above the bore of the barrel . They work well and keep everything aligned correctly .

Yes a short barrel has less of a cantilever effect on the trunnion and extension so it might work but why take a chance on screwing up a trunnion ,they are Very thin on the top already and that is the expensive and hard to replace part !
 

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PhD in Over-Engineering
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BFF makes a nice point. I had not even thought about the barrel extension. I do have a 16" barrel with no bearing replacement. It ran fine, but I stopped using it when this issue was brought to my attention. I'll probably sleeve it one day. Meanwhile, I dug up a drawing from Jon Moran's site, which illustrates the proper way to do these things.

I first saw this done at John McGuire's shop back a few years ago. He also pins the relocated bearing in place. I've also seen them welded all around the seam.

 

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That makes sense. I have a 8mm setup but wanted to convert it to 308 so I guess I will need to do a little more work in the machine shop. That diagram makes the process a little easier thanks for posting it.
 

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BeltFed GURU
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Lucky#13,
The two barrels in question (converted MG 34 ) are Johns`s work :tongue: .

Zammer ,
If you cut the bearing surface a little under size to the turn down on the barrel just heat the bearing up and it will drop right on and shrink tight and on firing it will stay tight because both the turn down and the bearing with grow evenly because of the heat .
 

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What we have in stock at Recon are John McGuire's handiwork The shortened barrel properly sleeved and the correct length shroud for $295 each set using Izzy 308/7.62 barrels. You guys are a wealth of knowledge for all of us. Kevin
 

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What we have in stock at Recon are John McGuire's handiwork The shortened barrel properly sleeved and the correct length shroud for $295 each set using Izzy 308/7.62 barrels. You guys are a wealth of knowledge for all of us. Kevin
Would you sell just a barrel if so what would price be?
 
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